Field of the Invention
The present invention relates to an ophthalmic lens and the method for manufacturing the same and particularly, relates to an ophthalmic lens having excellent deposit resistance and high hydrophilicity and a method for manufacturing the same.
Description of Related Art
In the early years, hard contact lens was mainly made of glass. The soft contact lens was therefore developed to improve the wearing discomfort of the hard contact lens. The soft contact lens can be classified into two categories, hydrogel contact lens and silicone hydrogel contact lens.
The increasing surface hydrophilicity of contact lens will increase the wearing comfort of contact lens. However, the increasing surface hydrophilicity of the contact lens will also increase the deposition of the protein and lipid in the tears onto the surface of the contact lens, thus results in reduction of the clarity of lens and the wearing comfort and even the occurrence of ocular allergy. Moreover, the bacteria on users' fingers are usually transferred to the soft contact lens and adhering thereon during wearing the contact lens, which will result in ocular infection thereafter. Therefore, there is a need for an ophthalmic lens with high hydrophilicity, deposit resistance and antimicrobial properties.
Several methods have been proposed in the state of the art to solve the problem of protein and/or lipid deposition, such as adding fluoro-containing monomers or zwitterionic materials into the composition for manufacturing the ophthalmic lens; treating the surface of the contact lens by plasma treatment; or modifying the surface of the contact lens by, for example, covalently bonding zwitterionic materials to the surface of the contact lens. The approaches mentioned above have various disadvantages. For example, it is known that the addition of fluoro-containing monomers to the composition for manufacturing the ophthalmic lens will lower the surface hydrophilicity of the formed lens; the addition of zwitterionic materials into the composition for manufacturing the ophthalmic lens will adversely affect the physical properties of ophthalmic lens and decrease the production yield; plasma treatment is conducted by high-cost equipment; the modification of lens surface will cause lens deformation and/or decrease the production yield and needs further cleaning step so that the manufacturing process thereof is complicated.
Recently, bio-compatible materials are widely used in medical devices, especially the bio-polymer materials. It proposes the use of polydopamine to modify the surface of the contact lens. However, because the color of the polydopamine is dark-blue, thus a brown hydrophilic layer will be formed on the polydopamine-modified surface of the contact lens. Therefore it suggests to control the concentration of the polydopamine for modifying the surface of contact lens in order to reduce the impact the optical properties of the contact lens.
Therefore, the present invention is to provide an ophthalmic lens having a novel antimicrobial hydrophilic layer which provides excellent deposit resistance, high hydrophilicity and desirable optical property, and a simple and high effective method for manufacturing the ophthalmic lens.